Over the past few decades, mobile communications have evolved from voice services to high-speed broadband data services. With further development of new types of businesses and applications, e.g. the mobile Internet and Internet of Things (IoT), the demands on data on mobile networks will continue to increase exponentially. Based on diversified business and application requirements in future mobile communications, wireless communication systems should meet a variety of requirements, such as throughput, latency, reliability, link density, cost, energy consumption, complexity, and coverage.
An LTE (Long-Term Evolution) system can support performing FDD (Frequency Division Duplex) operation on a pair of spectrums (e.g. performing downlink on one carrier and uplink on another carrier): It also supports TDD (Time Division Duplex) operation on an unpaired carrier. In a conventional TDD operation mode, only a limited number of configurations of uplink and downlink sub-frame allocations (corresponding to configuration 0 to configuration 6) are utilized. Adjacent areas use a same configuration, that is, with the same direction of transmission. The technology of eIMTA (enhanced interference mitigation and traffic adaptation) can configure semi-statically (at 10 ms or more) the uplink and downlink of the LTE system, and make adjacent areas use different configurations of TDD uplink and downlink sub-frame allocations. But these configurations are still limited to the several configurations described above.
Future wireless communication systems, such as the 5G/New Radio (NR) system, will support dynamic TDD operations, flexible Duplexing (or Duplexing flexibility) operations, and full Duplexing operations, in order to meet the fast adaptive requirements of the business and to further improve the efficiency of spectrum utilization. Taking dynamic TDD as an example, a dynamic TDD operation refers to dynamically or semi-dynamically changing the transmission direction as uplink or downlink, on the unpaired spectrum (or on the uplink or downlink carriers in the paired spectrum). Compared to eIMTA, dynamic TDD operations can support direction changes in a sub-frame level, a time slot level, or in an even more dynamic level. While an eIMTA system utilizes physical downlink control channel (PDCCH) to indicate TDD sub-frame configurations, a 5G/NR system will use group-common PDCCH to notify a group of terminals and/or users about some control information, e.g. slot format related information (SFI). For example, a base station (BS) in a 5G/NR system can indicate SFI via a group-common PDCCH to notify a group of terminals about channel structure information of a transmission link between the BS and each terminal within one or more time slots. The channel structure may include a pattern of transmission attributes, e.g. downlink (DL), uplink (UL), and/or OTHER of the transmission link.
There is no satisfactory solution in existing literatures or existing technologies for any of the following issues: (a) how the terminal can understand an SFI indication under different waveform parameter sets; (b) how the terminal can handle an OTHER filed in the channel structure, especially when a transmission direction indicated by the SFI conflicts with the transmission direction indicated by a user equipment (UE) specific downlink control information (DCI) and/or with the transmission direction under a semi-static configuration.